'We still need more movement,' Yvo de Boer, head of the U.N. Climate Change Secretariat, told a news conference at the end of two days of talks among 40 ministers from around the world on a deal meant to be agreed at the December 7-18 meeting in Denmark.

'Industrialized countries must raise their targets and financial commitments further...I look to the United States for a numerical mid-term target and a clear commitment on finance,' he told a news conference.

The United States is the second greenhouse gas emitter behind China but U.S. carbon-capping legislation is stalled in the U.S. Senate. Many nations say that Washington should promise a deep 2020 cut to help unlock a deal in Copenhagen."